LAUSR

Background Smartphone usage is indispensably beneficial to people’s everyday lives. However, excessive smartphone usage has been associated with physical and mental health problems. This study aimed to evaluate the association of smartphone usage with depressive symptoms, suicidal thoughts, and suicide attempts in Korean adolescents. Methods This cross-sectional study was conducted in 54,603 Korean adolescent participants (26,930 male and 27,673 female) in the Korea Youth Risk Behavior Survey in 2017 who reported their smartphone use. We performed multiple logistic regression analysis to evaluate the association of smartphone use with mental health after adjusting for relevant covariates. Results Among the participants, 25.6% of male students and 38.4% of female students reported using their smartphone for at least 30 hours per week. As time duration of smartphone usage increased, the risk of experiencing depressive symptoms, suicidal thoughts, and suicide attempt tended to increase, with odds ratios (95% confidence interval) of 1.18 (1.10–1.26), 1.18 (1.08–1.29), and 1.34 (1.11–1.60), respectively, for high smartphone usage compared with low smartphone usage. These associations remained significant with only slight change in odds ratios after consideration of problems that may be caused by smartphone usage, such as conflicts with family members or peers, or disturbance in school work. Conclusion Smartphone overuse was independently associated with an increased risk of mental health problems, which did not seem to be mediated by the problems caused by smartphone usage.